The following terms are used in this specification and have the following meaning:
TermMeaningC-ClassAn IP address block consisting of 256 consecutivenetworkaddressesaddressDNSDirectory Name Service. The naming services used onthe internet to map between symbolic names(www.example.com) and IP addresses.GeocodeThe process of taking geographical address information,such as a street level address and translating it into aprecise longitude and latitude.GeocodingThe precision of the geocoding, such as street level, townResolutionprovince or zip/postal-code. Each level of geocodingoffers better absolute precision and tothe margin of error.IP addressInternet Protocol Address (either IPv4 or IPv6) - theaddress system allowing internet applicationsto communicate.IPv4Original IP addressing, using 32 bits for the address.IPv6New improved IP addressing scheme,using 128 bits for the addressISPInternet Service ProviderLongitude-An addressing system for describing a position anywherelatitudeon the globe.Reverse DNSThe DNS service which allows one to retrieve a domainname given an IP ddress.PIPE/ARINOrganisations responsible for allocating IP addressesglobally. The responsibility is divided between4 organisations, RIPE for Europe, ARIN for America,APNIC for Asia Pacific, LACNIC for Latin AmericaTriangulationThe process of determining a location by somemeasurements obtained from multiple other knownlocations.
A number of Internet applications such as advertising using banners or paid listings depend on the ability to position the user in a geographical context. Due to the way the internet functions, majority access being largely anonymous, the most relevant piece of information that an application has to rely on to determine a geographic location is the IP address of the connecting user.
There are a number of existing methods for determining the approximate geographical locations of IP addresses. The RIPE/ARIN IP organisations maintain a database of the IP Ranges allocated to specific continents, countries and Internet Service Providers (ISPs). Some known methods of incremental improvements beyond this base data are:                Looking at the “Traceroute” information for individual IP addresses. “Traceroute” provides the ISP assigned names for the routers leading up to the terminating IP address. Many ISPs assign names which provide their support staff with an indication of the physical and geographical location of the routing equipment meaning that state, city, suburb or airport codes are therefore typically included in the name chosen for the router. There is however no agreed standard for such naming, and hence each ISP uses their own standard which needs to be known, derived or second guessed by an observer.        Looking at the transmission time (ping-time) between well known geographical locations and an IP address being investigated. The concept is that with the use of triangulation it is possible to determine the IP address location, assuming that the transmission time is a measure of direct distance between the known location and the IP address being pinged. This assumption is only correct in a well connected and well maintained network where there are little or no delays in transmission times (or consistent delays in transmission times over the respective transmission lines between the known location and the IP address being pinged. Despite the fact that the Internet is constantly developing better connectivity this method fails when two near-by points connecting via a remote point (e.g. London to Paris via New York).        Data mining from specialist sites. A number of specialist sites (TV listings, Online Car Shopping, Online Dating, etc.) require a user to enter post code information, or similar which defines a limited geographical area to which the user's IP address can be mapped.        
These approaches are limited by the constraints that they can only provide a best estimate of the geographical location of a user's IP address down to a city or suburb level and they assume that all IP addresses are of equal importance.